Cancer is a genetically complex and biologically heterogeneous group of disorders. It has become increasingly clear that the laboratory mouse, the best genetically defined experimental model organism for humans, presents a major opportunity for rapid advancement in understanding the genetic basis and underlying biology of cancer. The overall goal for our course is to train young scientists (predoctoral, postdoctoral trainees, new investigators) in the use of genetically defined laboratory mice as genetic tools for asking questions about gene function and the role of genetics in the biology of cancer. Students completing the course will acquire a working knowledge of: (1) mouse genetics and genomics, (2) growth control and cancer, (3) experimental design and the application of statistical genetics to complex trait analysis, (4) bioinformatics, (5) animal health and ethical considerations in working with mice, (6) basic mouse surgical techniques, and (7) mouse models for human cancer. How the mouse is used in the translation of basic research to the clinic will be emphasized. These Aims will be accomplished by offering an intensive 10-day course to 35 young investigators chosen for their outstanding research potential. They will interact with a group of prominent mouse geneticists and cancer biologists both from The Jackson Laboratory and other prominent institutions. The size of the class will be kept deliberately small in order to achieve a desirable level of student-faculty interaction. The course will be held annually during the last tw weeks of August at Highseas, The Jackson Laboratory's residential oceanfront conference facility. Lectures, discussions, workshops, and demonstrations will be held morning, afternoon, and evening for a total of approximately 72 hours of didactic and hands-on training. We are asking for a full five years of support in this application. The Jackson Laboratory is an NCI-designated Basic Research Cancer Center and has a long history of hosting advanced courses and scientific meetings. The annual short course on the Experimental Models of Human Cancer described in this application has been held annually since 1992.